The present invention pertains to apparatus for interconnection of members by means of matching threads, and more particularly pertains to an assembly apparatus for rapid interconnection of threaded members such as nuts and bolts. In one specific respect, the present invention pertains to an improved nut driver having a retractable nut spindle which extends through a nut holder on the outer end of the driver.
During high speed assembly operations wherein bolts are placed into preformed holes and nuts are then screwed onto the bolts, there is a need for apparatus which can automatically insert bolts in the holes and then apply nuts thereto, thus greatly increasing the rate at which such operations can be performed.
Among the components which can be useful in interconnecting nuts with bolts is a nut driver having means for gripping a nut so as to prevent free rotation thereof during attachment to a bolt, and also a nut spindle which passes through the threaded central channel of the nut and which retracts into the channel to make room for the shank of a bolt being installed therein. One form of nut driver having means for holding a nut and a spindle which passes through the central channel therein is disclosed in U.S. Pat. No. 3,489,041 to Hauenstein et al, but it should be noted that the spindle disclosed therein has an outer end portion that is shaped to fit into the hollow interior of a socket-like stud. Accordingly, the outermost tip of the spindle is not adapted for contact with the external end face on an ordinary screw, bolt, or stud that is not hollow, nor is the outermost tip adapted to retract through the threaded central channel of a nut being driven in order to make room for the bolt onto which the nut is screwed. It should also be noted that the manner of turning nuts on bolts as disclosed by Hauenstein et al involves use of ribs on a rotating member which engage notches in the nut, e.g. a notched circular nut as is used for securing a headphone jack in place. There is thus no recess on the driver into which the nut can fit, and no means are disclosed for holding and tightening hexagonal nuts. As a consequence, the nut driver disclosed in U.S. Pat. No. 3,489,041 is not regarded to be altogether satisfactory for interconnecting ordinary varieties of threaded nuts and bolts.
One object of the present invention is, therefore, to provide means for rapidly interconnecting first and second members that have matching threads, such as nuts and bolts, while also providing improved means for spindling and holding one of the first members while it is being threadedly interconnected with one of the second members.
Another object is to provide an assembly means which aligns a first and a second member having matching threads, and which then interconnects the two members by means of their threads.
Still another object is to provide assembly means for screwing nuts onto bolts, and including feed means whereby nuts and bolts are supplied to the assembly means one at a time and at a desired rate.
Yet another object is to provide means that can be actuated at will to automatically perform a sequence of steps whereby a nut and a bolt are displaced from respective feed means therefor and are then interconnected by means of their threads.
Even another object is to provide an improved nut driver for installing nuts on bolts, screws, studs, and the like.
Other objects and advantages of the present invention will become apparent from the following description and the accompanying drawings, but it will be understood that other accordant embodiments of the invention will become apparent which are not described and shown herein.